Dienone-phenol rearrangement
The dienone-phenol rearrangement is a name reaction in organic chemistry and was first published in 1921 by the German chemists Karl von Auwers and Karl Ziegler . The reaction describes the synthesis of substituted phenol from substituted dienone.
Overview reaction
Disubstituted cyclohexadienone reacts in acidic solution (or photochemically ) to form a disubstituted phenol:
Reaction mechanism
The mechanism is described in the literature:
The 4,4-disubstituted 2,5-cyclohexadien-1-one 1 is protonated , the reactive oxonium ion 2 being formed. Subsequent electron and atom rearrangement in the isomeric intermediate ( 3 ) yields the 3,4-disubstituted phenol 4 with elimination of a proton .
Individual evidence
- ↑ K. v. Auwers and K. Ziegler (1921), On hydrocarbons of the semibenzene group. Justus Liebigs Ann. Chem. , 425: 217-280. doi: 10.1002 / jlac.19214250302 .
- ↑ B. Miller and J. Baghdadchi (1987), Formation and rearrangement of 8a-benzyl-2-tert-butyl-1 (8aH) -naphthalenone, a ketone with a ring system consisting entirely of fused blocked aromatic rings The Journal of Organic Chemistry 52 (15), 3390-3394, doi: 10.1021 / jo00391a041 .
- ↑ Z. Guo and AG Schultz (2001), Preparation and Photochemical Rearrangements of 2-Phenyl-2,5-cyclohexadien-1-ones. An Efficient Route to Highly Substituted Phenols Organic Letters 3 (8), 1177-1180, doi: 10.1021 / ol015637h .
- ^ Z. Wang: Comprehensive organic name reactions and reagents Volume 1 . John Wiley, Hoboken (NJ) 2009, ISBN 978-0-470-28662-3 , pp. 897-899 .